package com.hll.file;

import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;

import javax.servlet.http.HttpServletRequest;
import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.*;

/**
 * 文件上传工具类
 *
 * @author yangdc
 * @date Apr 18, 2012
 *     <pre>
 * </pre>
 */
public class FileLoad2 {
  /** 表单字段常量 */
  public static final String FORM_FIELDS = "form_fields";
  /** 文件域常量 */
  public static final String FILE_FIELDS = "file_fields";
  // 上传临时路径
  private static final String TEMP_PATH = "/temp";
  // 最大文件大小
  private long maxSize = 1000000;
  // 定义允许上传的文件扩展名
  private Map<String, String> extMap = new HashMap<String, String>();
  // 文件保存目录相对路径
  private String basePath = "upload";
  // 文件的目录名
  private String dirName = "images";
  private String tempPath = basePath + TEMP_PATH;
  // 若不指定则文件名默认为 yyyyMMddHHmmss_xyz
  private String fileName;

  // 文件保存目录路径
  private String savePath;
  // 文件保存目录url
  private String saveUrl;
  // 文件最终的url包括文件名
  private String fileUrl;

  public FileLoad2() {
    // 其中images,flashs,medias,files,对应文件夹名称,对应dirName
    // key文件夹名称
    // value该文件夹内可以上传文件的后缀名
    extMap.put("images", "gif,jpg,jpeg,png,bmp");
    extMap.put("flashs", "swf,flv");
    extMap.put("medias", "swf,flv,mp3,wav,wma,wmv,mid,avi,mpg,asf,rm,rmvb");
    extMap.put("files", "doc,docx,xls,xlsx,ppt,htm,html,txt,zip,rar,gz,bz2");
  }

  /**
   * 文件上传
   *
   * @param request
   * @return infos info[0] 验证文件域返回错误信息 info[1] 上传文件错误信息 info[2] savePath info[3] saveUrl info[4]
   *     fileUrl
   */
  @SuppressWarnings("unchecked")
  public String[] uploadFile(HttpServletRequest request) {
    String[] infos = new String[5];
    // 验证
    infos[0] = this.validateFields(request);
    // 初始化表单元素
    Map<String, Object> fieldsMap = new HashMap<String, Object>();
    if (infos[0].equals("true")) {
      fieldsMap = this.initFields(request);
    }
    // 上传
    List<FileItem> fiList = (List<FileItem>) fieldsMap.get(FileLoad2.FILE_FIELDS);
    if (fiList != null) {
      for (FileItem item : fiList) {
        infos[1] = this.saveFile(item);
      }
      infos[2] = savePath;
      infos[3] = saveUrl;
      infos[4] = fileUrl;
    }
    return infos;
  }

  /**
   * 上传验证,并初始化文件目录
   *
   * @param request
   */
  private String validateFields(HttpServletRequest request) {
    String errorInfo = "true";
    // boolean errorFlag = true;
    // 获取内容类型
    String contentType = request.getContentType();
    int contentLength = request.getContentLength();
    // 文件保存目录路径
    savePath = request.getSession().getServletContext().getRealPath("/") + basePath + "/";
    // 文件保存目录URL
    saveUrl = request.getContextPath() + "/" + basePath + "/";
    File uploadDir = new File(savePath);
    if (contentType == null || !contentType.startsWith("multipart")) {
      // TODO
      System.out.println("请求不包含multipart/form-data流");
      errorInfo = "请求不包含multipart/form-data流";
    } else if (maxSize < contentLength) {
      // TODO
      System.out.println("上传文件大小超出文件最大大小");
      errorInfo = "上传文件大小超出文件最大大小[" + maxSize + "]";
    } else if (!ServletFileUpload.isMultipartContent(request)) {
      // TODO
      errorInfo = "请选择文件";
    } else if (!uploadDir.isDirectory()) { // 检查目录
      // TODO
      errorInfo = "上传目录[" + savePath + "]不存在";
    } else if (!uploadDir.canWrite()) {
      // TODO
      errorInfo = "上传目录[" + savePath + "]没有写权限";
    } else if (!extMap.containsKey(dirName)) {
      // TODO
      errorInfo = "目录名不正确";
    } else {
      // .../basePath/dirName/
      // 创建文件夹
      savePath += dirName + "/";
      saveUrl += dirName + "/";
      File saveDirFile = new File(savePath);
      if (!saveDirFile.exists()) {
        saveDirFile.mkdirs();
      }
      // .../basePath/dirName/yyyyMMdd/
      SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd");
      String ymd = sdf.format(new Date());
      savePath += ymd + "/";
      saveUrl += ymd + "/";
      File dirFile = new File(savePath);
      if (!dirFile.exists()) {
        dirFile.mkdirs();
      }

      // 获取上传临时路径
      tempPath = request.getSession().getServletContext().getRealPath("/") + tempPath + "/";
      File file = new File(tempPath);
      if (!file.exists()) {
        file.mkdirs();
      }
    }

    return errorInfo;
  }

  /**
   * 处理上传内容
   *
   * @param request
   * @param
   * @return
   */
  //	@SuppressWarnings("unchecked")
  private Map<String, Object> initFields(HttpServletRequest request) {

    // 存储表单字段和非表单字段
    Map<String, Object> map = new HashMap<String, Object>();

    // 第一步：判断request
    boolean isMultipart = ServletFileUpload.isMultipartContent(request);
    // 第二步：解析request
    if (isMultipart) {
      // Create a factory for disk-based file items
      DiskFileItemFactory factory = new DiskFileItemFactory();

      // 阀值,超过这个值才会写到临时目录,否则在内存中
      factory.setSizeThreshold(1024 * 1024 * 10);
      factory.setRepository(new File(tempPath));

      // Create a new file upload handler
      ServletFileUpload upload = new ServletFileUpload(factory);

      upload.setHeaderEncoding("UTF-8");

      // 最大上传限制
      upload.setSizeMax(maxSize);

      /* FileItem */
      List<FileItem> items = null;
      // Parse the request
      try {
        items = upload.parseRequest(request);
      } catch (FileUploadException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
      }

      // 第3步：处理uploaded items
      if (items != null && items.size() > 0) {
        Iterator<FileItem> iter = items.iterator();
        // 文件域对象
        List<FileItem> list = new ArrayList<FileItem>();
        // 表单字段
        Map<String, String> fields = new HashMap<String, String>();
        while (iter.hasNext()) {
          FileItem item = iter.next();
          // 处理所有表单元素和文件域表单元素
          if (item.isFormField()) { // 表单元素
            String name = item.getFieldName();
            String value = item.getString();
            fields.put(name, value);
          } else { // 文件域表单元素
            list.add(item);
          }
        }
        map.put(FORM_FIELDS, fields);
        map.put(FILE_FIELDS, list);
      }
    }
    return map;
  }

  /**
   * 保存文件
   *
   * @param
   * @param
   * @return
   */
  private String saveFile(FileItem item) {
    String error = "true";
    String fileName = item.getName();
    String fileExt = fileName.substring(fileName.lastIndexOf(".") + 1).toLowerCase();

    if (item.getSize() > maxSize) { // 检查文件大小
      // TODO
      error = "上传文件大小超过限制";
    } else if (!Arrays.<String>asList(extMap.get(dirName).split(",")).contains(fileExt)) { // 检查扩展名
      error = "上传文件扩展名是不允许的扩展名。\n只允许" + extMap.get(dirName) + "格式。";
    } else {
      String newFileName;
      if ("".equals(fileName.trim())) {
        SimpleDateFormat df = new SimpleDateFormat("yyyyMMddHHmmss");
        newFileName = df.format(new Date()) + "_" + new Random().nextInt(1000) + "." + fileExt;
      } else {
        newFileName = fileName + "." + fileExt;
      }
      // .../basePath/dirName/yyyyMMdd/yyyyMMddHHmmss_xxx.xxx
      fileUrl = saveUrl + newFileName;
      try {
        File uploadedFile = new File(savePath, newFileName);

        item.write(uploadedFile);

        /*
         * FileOutputStream fos = new FileOutputStream(uploadFile); // 文件全在内存中 if (item.isInMemory()) { fos.write(item.get()); } else { InputStream is = item.getInputStream(); byte[] buffer =
         * new byte[1024]; int len; while ((len = is.read(buffer)) > 0) { fos.write(buffer, 0, len); } is.close(); } fos.close(); item.delete();
         */
      } catch (IOException e) {
        e.printStackTrace();
        System.out.println("上传失败了！！！");
      } catch (Exception e) {
        e.printStackTrace();
      }
    }
    return error;
  }

  /** **********************get/set方法********************************* */
  public String getSavePath() {
    return savePath;
  }

  public String getSaveUrl() {
    return saveUrl;
  }

  public long getMaxSize() {
    return maxSize;
  }

  public void setMaxSize(long maxSize) {
    this.maxSize = maxSize;
  }

  public Map<String, String> getExtMap() {
    return extMap;
  }

  public void setExtMap(Map<String, String> extMap) {
    this.extMap = extMap;
  }

  public String getBasePath() {
    return basePath;
  }

  public void setBasePath(String basePath) {
    this.basePath = basePath;
    tempPath = basePath + TEMP_PATH;
  }

  public String getDirName() {
    return dirName;
  }

  public void setDirName(String dirName) {
    this.dirName = dirName;
  }

  public String getTempPath() {
    return tempPath;
  }

  public void setTempPath(String tempPath) {
    this.tempPath = tempPath;
  }

  public String getFileUrl() {
    return fileUrl;
  }

  public String getFileName() {
    return fileName;
  }

  public void setFileName(String fileName) {
    this.fileName = fileName;
  }
}
